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Date:   Tue, 14 Jul 2020 12:13:17 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     "Westergreen, Dalon" <dalon.westergreen@intel.com>
Cc:     "mkubecek@suse.cz" <mkubecek@suse.cz>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "Tan, Ley Foon" <ley.foon.tan@intel.com>,
        "See, Chin Liang" <chin.liang.see@intel.com>,
        "Nguyen, Dinh" <dinh.nguyen@intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "Ooi, Joyce" <joyce.ooi@intel.com>,
        "thor.thayer@linux.intel.com" <thor.thayer@linux.intel.com>
Subject: Re: [PATCH v4 09/10] net: eth: altera: add msgdma prefetcher
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On Tue, 14 Jul 2020 18:51:15 +0000 Westergreen, Dalon wrote:
> > I've seen vendors abuse fields of ethtool --coalesce to configure
> > similar settings. tx-usecs-irq and rx-usecs-irq, I think. Since this
> > part of ethtool API has been ported to netlink, could we perhaps add 
> > a new field to ethtool --coalesce?  
> 
> I don't think this is necessary, i think just having a module parameter
> meets our needs.  I don't see a need for the value to change on a per
> interface basis.  This was primarily used during testing / bringup.

It's hard to tell which knobs users will find worth turning therefore
the testing / bringup justification unfortunately has little bearing on
our upstream interface choices.

We try hard to avoid module parameters in networking drivers, so if you
want this tunable upstream a proper user interface will be required.